In Canada you cannot be refused employment on the basis of these proscribed attributes: sex, religion, age, marital status, sexual orientation, or ethnicity. You may be refused employment where predetermined bona fide operational requirements preclude employment of certain people due to the inherent risks to safety and health, not necessarily of the person applying but to those who may depend on that person's ability to work safely effectively. This would include, as examples, physical disability or education.
If you are refused employment in Canada solely on the basis of any of the proscribed attributes mentioned at the outset, you will have a case with the Human Rights Commission.
I would think you might have a case against UP, but your own laws will be the determinant, and even then the absolute determinant is what your Supreme Court decides it should be.
-Crandell